/32 network route
Posted on 2014-02-01
I have an odd situation, in our private network our supplier at our request has set up a couple of /32 network routes.
i.e. 10.1.1.0/24 is the LAN network, we have 2 host with fixed IP's that we needed to move to another site. To accommodate this move without changing IP's on the moved host our private network supplied created 2x /32 routes 10.1.1.97/32 and 10.1.1.150/32. This worked a treat.
My puzzling issue is, I have servers in the 10.1.1.0/24 network that are learning the routes for 10.1.1.97 and 10.1.1.150. I cannot determine how they are learning these routes. On the 10.1.1.0/24 network only some clients needed to learn the new /32 routes, this was done by DHCP and option 121.
On the servers which remained on site:
There is no static route entry on these server hosts pointing to the /32 for 97 & 150.
I believe proxy arp is not configured on the gateway CISCO routers, also there is 4 hops between the 10.1.1.0/24 LAN and the new network that 97 & 150 are routed to, so proxy arp should not work anyway as the destination network is not directly attached to the LAN router.
arp -a show the mac address of the gateway router, same as default gateway, for 97 & 150.
Deleting arp for 97 & 150 immediately relearns same arp entry.
The /32 routes were required for an urgent application migration from a remote site to a data centre where over 250 client connections were configured using static IP, we did not have time to update clients until after the migration.
Any assistance is appreciated.